Funding for this research was provided by:
National Natural Science Foundation of China (U1504625)
Foundation of Henan Educational Committee (12A510003)
Youth backbone teacher training program in He’nan province (2017GGJS021)
Program for Innovative Research Team in Science and Technology in University of Henan Province (19IRTSTHN019)
Text and Data Mining valid from 2018-08-30
Received: 28 May 2018
Accepted: 21 August 2018
First Online: 30 August 2018
: The authors declare that they have no competing interests.
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